IRS20124SPBF International Rectifier, IRS20124SPBF Datasheet - Page 23

• Manufacturer Part Number: IRS20124SPBF
• Description: IC DIGITAL AUDIO DRIVER 14-SOIC
• Manufacturer: International Rectifier
• Type: MOSFET Driverr

Specifications of IRS20124SPBF

• Applications: Amplifiers, Receivers
• Mounting Type: Surface Mount
• Package / Case: 14-SOIC (3.9mm Width), 14-SOL
• Current, Output: 1
• Current, Output, High Level: 1 A
• Current, Output, Low Level: 1.2 A
• Delay, Propagation, Turn-off: 80 ns
• Delay, Propagation, Turn-on: 80 ns
• Driver Type: Audio
• Package: 14-Lead SOIC
• Package Type: 14-Lead SOIC
• Temperature, Operating: –40 to +124 °C
• Thermal Resistance Junction/ambient: 100 °C/W
• Thermal Resistance, Junction To Ambient: 100 °C/W
• Time, Fall, Turn-off: 35 ns
• Time, Rise, Turn-on: 40 ns
• Time, Turn-off Delay: 80 ns
• Time, Turn-on: 80 ns
• Time, Turn-on Delay: 80 ns
• Voltage, Output, High Level: 1.2 V
• Voltage, Output, Low Level: 0.1 V
• Voltage, Supply: 200 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

How to set OC Threshold
The positive and negative trip thresholds for bi-
directional current sensing are set by the voltages
at OC
The trip threshold voltages, V
determined by the required trip current levels, I
I
Since the sensed voltage of V
2.21 V internally and compared with the voltages
fed to the OC
value of OC
V
The same relation holds between OC
V
In general, R
efficient that needs to be considered when the
threshold level is being set. Please also note that,
www.irf.com
TRIP-
External Resistor Network to Set OC Threshold
OCSET1
OCSET2
, and R
>0.5mA
SET1
= V
= V
and OC
SOC+
SOC-
DS(ON)
SET1
DS(ON)
SET1
+ 2.21 V = I x R
R3
R4
R5
with respect to COM is
+ 2.21 V = I x R
in the low side MOSFET.
SET2
has a positive temperature co-
and OC
.
Vcc
OC
OC
COM
SET2
SET1
SET2
SOC+
pins, the required
s
DS(ON)
DS(ON)
is shifted up by
and V
SET2
+ 2.21 V
and V
+ 2.21 V
SOC+,
SOC-,
TRIP+
are
in the negative load current direction, the sensing
voltage at the V
ode of the low side MOSFET as explained later.
Design Example
This example demonstrates how to use the exter-
nal resistor network to set I
±11 A, using a MOSFET that has R
V
V
The total resistance of resistor network is based
on the voltage at the V cc and required bias cur-
rent in this resistor network.
R
The expected voltage across R3 is Vcc- V
= 12 V - 2.87 V=9.13 V. Similarly, the voltages
across R4 is V
=1.32 V, and the voltage across R5 is V
V respectively.
R3 =9.13 V/ I
R4 =1.32 V/ I
R5 =1.55 V/ I
Choose R3 9.09 k R4=1.33 k , R5=1.54 k
from E-96 series.
Consequently, actual threshold levels are
V
V
Resisters with 1% tolerances are recommended.
ISET1
ISET2
total
SOC+
SOC-
x 60
=R3 + R4 + R5 = Vcc / I
= V
= V
V
=1.55 V gives I
=2.88 V gives I
12 V
TH
TH-
+ + 2.21 V = I
+ 2.21 V = I
bias
bias
bias
2.21 V = 2.87 V
SOC+
s
IRS20124S(PbF)
node is limited by the body di-
2.21 V = 1.55 V
9.13k
1.32k
1.55k
- V
TRIP-
TRIP+
12 k
SOC-
TRIP-
= -11.0 A
TRIP+
= 11.2 A
TRIP+
x R
bias
= 2.87 V - 1.55 V
x R
DS(ON)
and I
DS(ON)
DS(ON)
TRIP-
ISET2
2.21 V
=6
2.21V
= 1.55
to be
ISET1
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